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arXiv · 1206.5128

Robust optical emission polarization in MoS2 monolayers through selective valley excitation

G. Sallen·L. Bouet·X. Marie·G. Wang·C. R. Zhu·W. P. Han·Y. Lu·P. H. Tan·T. Amand·B. L. Liu·B. Urbaszek
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Abstract

We report polarization resolved photoluminescence from monolayer MoS2, a two-dimensional, non-centrosymmetric crystal with direct energy gaps at two different valleys in momentum space. The inherent chiral optical selectivity allows exciting one of these valleys and close to 90% polarized emission at 4K is observed with 40% polarization remaining at 300K. The high polarization degree of the emission remains unchanged in transverse magnetic fields up to 9T indicating robust, selective valley excitation.

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G. Sallen, L. Bouet, X. Marie, G. Wang, C. R. Zhu, W. P. Han, Y. Lu, P. H. Tan, T. Amand, B. L. Liu, B. Urbaszek. 2012-06-22. Robust optical emission polarization in MoS2 monolayers through selective valley excitation. https://doi.org/10.1103/physrevb.86.081301

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